Hydrocarbon conversion catalyst and its use

ABSTRACT

There is provided catalysts and conversion processes for converting hydrocarbons using the catalysts. The catalysts comprises a first alumino-phosphospho-molecular sieves and a binder comprising a second alumino-phopho-molecular sieves. Exemplary conversion processes include the conversion of oxygenates to olefins, dewaxing, reforming, dealkylation, dehydrogenation, transalkylation, alkylation, and isomerization.

This application is a continuation of application Ser. No. 09/328,724,filed Jun. 9, 1999, now abandoned, which is a divisional of applicationSer. No. 08/865,635, filed May 29, 1997, now U.S. Pat. No. 5,972,203.

FIELD OF INVENTION

This invention relates to crystalline alumino-phospho-molecular sievesthat are bound by crystalline alumino-phospho-molecular sieves and theiruse in hydrocarbon conversion processes.

BACKGROUND OF THE INVENTION

Crystalline microporous molecular sieves, both natural and synthetic,have been demonstrated to have catalytic properties for various types ofhydrocarbon conversion processes. In addition, the crystallinemicroporous molecular sieves have been used as adsorbents and catalystcarriers for various types of hydrocarbon conversion processes, andother applications. These molecular sieves are ordered, porous,crystalline material having a definite crystalline structure asdetermined by x-ray diffraction, within which there are a large numberof smaller cavities which may be interconnected by a number of stillsmaller channels or pores. The dimensions channels of these pores aresuch as to allow adsorption of molecules with certain dimensions whilerejecting those with larger dimensions. The interstitial spaces orchannels formed by the crystalline network enable molecular sieves, tobe used as molecular sieves in separation processes, catalysts andcatalyst supports in a wide variety of hydrocarbon conversion processes.

One family of crystalline microporous molecular sieves is molecularsieves containing framework tetrahedral units of silica (SiO₂) andoptionally alumina (AlO₂). Another family of crystalline microporousmolecular sieves contain framework tetrahedral units of alumina (AlO₂)and phosphorous (PO₂). These molecular sieves are discussed in“Introduction To Zeolite Science and Practice”, (H. van Bekkum, E. M.Flanigen, J. C. Jansen ed. 1991) which is hereby incorporated byreference. Examples of such ALPO-based molecular sieves (“ABMS”) includeSAPO, ALPO, MeAPO, MeAPSO, ELAPO, and ELAPSO. The composition of thesemolecular sieves is disclosed in Table I below:

TABLE 1 Compositional Acronyms for ALPO₄-Based Materials (Exemplary Meor Acronym Framework T-Atoms El T-Atoms) AlPO Al, P SAPO Si, Al, P MeAPOMe, Al, P (Co, Fe, Mg, Mn, Zn) MeAPSO Me, Al, P, Si (Co, Fe, Mg, Mn, Zn)ElAPO El, Al, P (As, B, Be, Ga, Ge, Li, Ti) ElAPSO El, Al, P, Si (As, B,Be, Ga, Ge, Li, Ti)

Within a pore of the crystalline molecular sieve, hydrocarbon conversionreactions such as paraffin isomerization, olefin skeletal or double bondisomerization, disproportionation, alkylation, and transalkylation ofaromatics are governed by constraints imposed by the channel size of themolecular sieve. Reactant selectivity occurs when a fraction of thefeedstock is too large to enter the pores to react; while productselectivity occurs when some of the products can not leave the channelsor do not subsequently react. Product distributions can also be alteredby transition state selectivity in which certain reactions can not occurbecause the reaction transition state is too large to form within thepores. Selectivity can also result from configuration constraints ondiffusion where the dimensions of the molecule approach that of the poresystem. Non-selective reactions on the surface of the molecular sieve,such reactions on the surface acid sites of the molecular sieve, aregenerally not desirable as such reactions are not subject to the shapeselective constraints imposed on those reactions occurring within thechannels of the molecular sieve.

ABMS have been used in the past as catalysts for hydrocarbon conversion.For instance, U.S. Pat. No. 4,741,820 involves the use in a reformingprocess using intermediate pore size molecular sieves such as SAPO whichare bound by amorphorous material.

ABMS are usually prepared by crystallization of a supersaturatedsynthesis mixture. The resulting crystalline product is then dried andcalcined to produce the molecular sieve powder. Although the powder hasgood adsorptive properties, its practical applications are severelylimited because it is difficult to operate fixed beds with the powder.Therefore, prior to using the powder in commercial processes, thecrystals are usually bound.

The powder is typically bound by forming aggregate of the molecularsieve such as a pill, sphere, or extrudate. The extrudate is usuallyformed by extruding the ABMS in the presence of an amorphorous binderand drying and calcining the resulting extrudate. The binder materialsused are resistant to the temperatures and other conditions, e.g.,mechanical attrition, which occur in various hydrocarbon conversionprocesses. Examples of binder materials include amorphous materials suchas alumina, silica, titania, and various types of clays. It is generallynecessary that the ABMS be resistant to mechanical attrition, that is,the formation of fines which are small particles, e.g., particles havinga size of less than 20 microns.

Although such bound aggregates have much better mechanical strength thanthe powder, when such a bound material is used in a catalytic conversionprocess, the performance of the catalyst, e.g., activity, selectivity,activity maintenance, or combinations thereof, can be reduced because ofthe binder. For instance, since the binder is typically present in anamount of up to about 50 wt. % of crystals, the binder dilutes theadsorption properties of the material. In addition, since the boundmolecular sieve is prepared by extruding or otherwise forming themolecular sieve with the binder and subsequently drying and calciningthe extrudate, the amorphous binder can penetrate the pores of themolecular sieve or otherwise block access to the pores of the molecularsieve, or slow the rate of mass transfer to the pores of the molecularsieve which can reduce the effectiveness of the molecular sieve whenused in hydrocarbon conversion processes and other applications.Furthermore, when the bound molecular sieve is used in catalyticconversion processes, the binder may affect the chemical reactions thatare taking place within the molecular sieve and also may itself catalyzeundesirable reactions which can result in the formation of undesirableproducts.

SUMMARY OF THE INVENTION

The present invention is directed to an ABMS bound ABMS catalyst whichcomprises first crystals of a first ABMS and a binder comprising secondcrystals of second ABMS and the use of the catalyst in hydrocarbonconversion processes. The structure type of the first ABMS can be thesame as the second ABMS or can be different. The acidity of the secondABMS is preferably carefully controlled e.g., the acidity of the secondABMS can be the same as the first ABMS crystals or the acidity of theABMS crystals can be higher or lower than the first ABMS crystals, sothat the performance of the catalyst is further enhanced.

The catalyst of the present invention finds particular application inhydrocarbon conversion processes where catalyst acidity in combinationwith ABMS structure are important for reaction selectivity. Examples ofsuch processes include catalytic cracking, alkylation, dealkylation,dehydrogenation, disproportionation, and transalkylation reactions. Thecatalyst of the present invention can also be used in other hydrocarbonconversion processes in which carbon containing compounds are changed todifferent carbon containing compounds. Examples of such processesinclude hydrocracking, isomerization, dewaxing, oxygenate conversion,oligomerization, and reforming processes.

DETAILED DESCRIPTION OF THE INVENTION

The catalyst of the present invention comprises first crystals of afirst ABMS and a binder comprising second crystals of a second ABMS.Typical ABMS catalysts used in hydrocarbon conversion processes arenormally bound with silica or alumina or other commonly used amorphousbinders to enhance the mechanical strength of the ABMS.

Unlike typical crystalline molecular sieve catalysts used in hydrocarbonconversion processes which are normally bound with silica or alumina orother commonly used amorphous binders to enhance its mechanicalstrength, the catalyst of the present invention generally does notcontain significant amounts of amorphous binders. Preferably, thecatalysts contain less than 10 percent by weight, based on the weight ofthe first and second ABMS, of non-crystalline molecular sieve binder,more preferably contains less than 5 percent by weight, and, mostpreferably, the catalyst is substantially free of non-crystallinemolecular sieve binder. Preferably, the second ABMS crystals bind thefirst ABMS crystals by adhering to the surface of the first ABMScrystals thereby forming a matrix or bridge structure which also holdsthe first crystals particles together. More preferably, the second ABMSparticles bind the first ABMS by intergrowing so as to form a, coatingor partial coating on the larger first ABMS crystals and, mostpreferably, the second ABMS crystals bind the first ABMS crystals byintergrowing to form an attrition resistant over-growth over the firstABMS crystals.

Although the invention is not intended to be limited to any theory ofoperation, it is believed that one of the advantages of the ABMS boundABMS catalyst of the present invention is obtained by the second ABMScrystals controlling the accessibility of the acid sites on the externalsurfaces of the first ABMS to reactants. Since the acid sites existingon the external surface of a ABMS catalyst are not shape selective,these acid sites can adversely affect reactants entering the pores ofthe ABMS and products exiting the pores of the ABMS. In line with thisbelief, since the acidity and structure type of the second ABMS can becarefully selected, the second ABMS does not significantly adverselyaffect the reactants exiting the pores of the first ABMS which can occurwith conventionally bound ABMS catalysts and may beneficially affect thereactants exiting the pores of the first ABMS. Still further, since thesecond ABMS is not amorphous but, instead, is a molecular sieve,hydrocarbons may have increased access to the pores of the first ABMSduring hydrocarbon conversion processes.

The terms “acidity”, “lower acidity” and “higher acidity” as applied tocrystalline molecular sieve are known to persons skilled in the art. Theacidic properties of crystalline molecular sieves are well known.However, with respect to the present invention, a distinction must bemade between acid strength and acid site density. Acid sites of acrystalline molecular sieves such as ABMS can be a Bronsted acid and/ora Lewis acid. The density of the acid sites and the number of acid sitesare important in determining the acidity of the ABMS. Factors directlyinfluencing the acid strength are (i) the chemical composition of theABMS framework, i.e., relative concentration and type of tetrahedralatoms, (ii) the concentration of the extra-framework cations and theresulting extra-framework species, (iii) the local structure of theABMS, e.g., the pore size and the location, within the crystal orat/near the surface of the ABMS, and (iv) the pretreatment conditionsand presence of co-adsorbed molecules. As used herein, the terms“acidity”, “lower acidity” and “higher acidity” refers to theconcentration of acid sites irregardless of the strength of such acidsites which can be measured by ammonia absorption.

The term “average particle size” as used herein, means the arithmeticaverage of the diameter distribution of the crystals on a volume basis.

First and second ABMS suitable for used in the catalyst of the presentinvention include large pore ABMS, intermediate pore size ABMS, andsmall pore size ABMS. These crystalline molecular sieves are describedin “Atlas of Zeolite Structure Types”, eds. W. H. Meier and D. H. Olson,Buttersworth-Heineman, Third Edition, 1992, which is hereby incorporatedby reference. Large pore ABMS generally have a pore size greater thanabout 7 Å and includes, for example, VFI, AET, AFI, AFO, ATS, FAU,structure type ABMS. Examples of large pore ABMS include ALPO-8,ALPO-41, SAPO-37, ALPO-37, ALPO-5, SAPO-5, ALPO-54, and MAPO-36. Mediumpore size ABMS generally have a pore size from about 7 Å to about 5 Å toabout 6.8 Å; and includes for example AEL, AFR, AFS, AFY, ATO, AFY, andAPD structure type ABMS. Examples of medium pore ABMS include ELAPSO-11,ELAPSO-31, ELAPSO-40, ELAPSO-41, CoAPSO-11, CoAPSO-31, FeAPSO-11,FeAPSO-31, MgAPSO-11, MgAPSO-31, MnAPSO-11, MnAPSO-31, TiAPSO-11,ZnAPSO-11, ZnAPSO-31, CoMgAPSO-11, CoMnMgAPSO-11, MeAPO-11, TiAPO-11,TiAPO-31, ELAPO-11, ELAPO-31, ELAPO-40, ELAPO-41, SAPO-11, SAPO-31,SAPO-40, SAPO-41, ALPO-31, and ALPO-11. A small pore size ABMS has apore size from about 3 Å to about 5.0 Å and includes, for example, AEI,AFT, APC, ATN, ATT, ATV, AWW, BIK, CAS, CHA, CHI, DAC, DDR, EDI, ERI,GOO, KFI, LEV, LOV, LTA, MON, PAU, PHI, RHO, ROG, and THO. Examples ofsmall pore ABMS include ALPO-17, ALPO-18, ALPO-52, ALPO-22, and ALPO-25.

The first ABMS will preferably have acidic activity and therefore willpreferably be an ABMS that has an additional metal incorporated into theAlPO₄ lattice such as SAPO, MeAPSO, or ELAPSO. Examples of preferredfirst ABMS include SAPO-34, SAPO-11, GaSAPO-11, ZnSAPO-11, SAPO-17,NiSAPO-34, SAPO-5.

The structure type of the first ABMS will depend on the particularhydrocarbon process in which the catalyst is used. For example, when thecatalyst is utilized for dewaxing, the first ABMS is preferably SAPO-11or SAPO-40.

The average particle size of the first crystals is preferably from about0.1 to about 15 microns. In many applications, the average particle sizeis preferably from about 1 to about 6 microns.

The structure type of the second ABMS can be the same or can bedifferent from the first ABMS. Preferably, the second ABMS will have lowacidity and more preferably will be substantially non-acidic. Thepreferred non-acidic ABMSs are aluminophosphates such as ALPO-17,ALPO-18, ALPO-11, ALPO-5, ALPO-41, GaALPO-11, ZnALPO-11. The pore sizeof the second ABMS will preferably be a pore size that does notsignificantly restrict access of the hydrocarbon feedstream to the poresof the first ABMS. For instance, when the materials of the feedstreamwhich are to be converted have a size from 5 Å to 6.8 Å, the second ABMSwill preferably be a large pore size ABMS or a intermediate pore sizeABMS.

The second ABMS is preferably present in the catalyst in an amount inthe range of from about 10 to about 60% by weight based on the weight ofthe first ABMS but the amount of second ABMS present will usually dependon the hydrocarbon process in which the catalyst is utilized. Morepreferably, the amount of second ABMS present in an amount of from about20 to about 50% by weight.

The second ABMS crystals preferably have a smaller size than the firstABMS crystals. The second ABMS crystals preferably have an averageparticle size of less than 1 micron, preferably from about 0.1 to lessthan 0.5 micron. The second ABMS crystals, in addition to binding thefirst ABMS particles and maximizing the performance of the catalyst willpreferably intergrow and to form an over-growth which coats or partiallycoats the first ABMS. Preferably, the coating will be resistant toattrition.

The catalysts of the present invention are preferably prepared by athree step procedure. The first step involves the synthesis of the firstABMS. Processes for preparing the first ABMS are known in the art.

In the next step, a alumina-bound ABMS is prepared preferably by mixinga mixture comprising the ABMS crystals, alumina, water and optionally anextrusion aid until a homogeneous composition in the form of anextrudable paste develops. The alumina binder used in preparing thealumina bound ABMS aggregate is preferably a alumina sol. The amount ofABMS in the extrudate when dry will range from about 30 to 90% byweight, more preferably from about 40 to 90% by weight, with the balancebeing primarily alumina, e.g., about 10 to 60% by weight alumina.

The resulting paste is then molded, e.g. extruded, and cut into smallstrands, e.g., approximately 2 mm diameter extrudates, which are driedat 100-150° C. for a period of 4-12 hours. Preferably the driedextrudates are then calcined in air at a temperature of from about 400°C. to 550° C. for a period of from about 1 to 10 hours. This calcinationstep also destroys the extrusion aid if present.

Optionally, the alumina-bound aggregate can be made into a very smallcrystals which have application in fluid bed processes such as catalyticcracking. This preferably involves mixing the ABMS with a aluminacontaining matrix solution so that an aqueous solution of ABMS andalumina binder is formed which can be sprayed dried to result in smallfluidizable alumina-bound aggregate crystals. Procedures for preparingsuch aggregate crystals are known to persons skilled in the art. Anexample of such a procedure is described by Scherzer (Octane-EnhancingZeolitic FCC Catalysts, Julius Scherzer, Marcel Dekker, Inc. New York,1990). The fluidizable alumina-bound aggregate crystals, like thealumina bound extrudates described above, would then undergo the finalstep described below to convert the alumina binder to a second ABMS.

The final step in the three step catalyst preparation process is theconversion of the alumina present in the alumina-bound catalyst to asecond ABMS which serves to bind the residual the ABMS crystalstogether. To prepare the catalyst, the alumina-bound aggregate ispreferably first aged in an appropriate aqueous solution at elevatedtemperature. Next, the contents of the solution and the temperature atwhich the aggregate is aged should be selected to convert the amorphousalumina binder into a second ABMS. The newly-formed ABMS is produced ascrystals. The crystals may grow on and/or adhere to the initial ABMScrystals, and may also be produced in the form of new intergrowncrystals, which are generally much smaller than the initial crystals,e.g., of sub-micron size. These newly formed crystals may grow togetherand interconnect thereby causing the larger crystals to become boundtogether.

The nature of the ABMS formed in the secondary synthesis conversion ofthe alumina to ABMS may vary as a function of the composition of thesecondary synthesis solution and synthesis aging conditions. Thesecondary synthesis solution is an aqueous ionic solution containing asource of phosphoric acid and a templating agent sufficient to convertthe alumina to the desired ABMS.

The catalyst of the present invention may be further ion exchanged as isknown in the art either to replace at least in part the original alkalimetal present in the first ABMS with a different cation, e.g., a Group1B to VIII Periodic Table metal such as nickel, copper, zinc, palladium,platinum, calcium or rare earth metal, or to provide a more acidic formof the catalyst by exchange of alkali metal with intermediate ammonium,followed by calcination to remove ammonia and acidic hydrogen form. Theacidic form may be readily prepared by ion exchange using a suitableacidic reagent such as ammonium nitrate. The catalyst may then becalcined at a temperature of 400-550° C. for a period of 10-45 hours toremove ammonium cations. Ion exchange is preferably conducted afterformation of the catalysts. Particularly preferred cations are thosewhich render the material catalytically active, especially for certainhydrocarbon conversion reactions. These include hydrogen, rare earthmetals, and metals of Groups IIA, IIIA, IVA, VA, IB, IIB, IIIB, IVB, VB,VIB, VIIB, and VIII of the Periodic Table of the Elements. Examples ofsuitable metals include platinum, palladium, rhodium, iridium, iron,molydenium, cobalt, tungsten, nickel, manganese, titanium, zirconium,vanadium, hafnium, zinc, tin, lead, chromium, etc. The catalyticallyactive metal is preferably present in an amount of from about 0.05 toabout 3.0 weight percent based on the weight of first ABMS.

The catalyst of the present invention can be used in processinghydrocarbon feedstocks. Hydrocarbon feed-stocks contain carbon compoundsand can be from many different sources, such as virgin petroleumfractions, recycle petroleum fractions, tar sand oil, and, in general,can be any carbon containing fluid susceptible to zeolitic catalyticreactions. Depending on the type of processing the hydrocarbon feed isto undergo, the feed can contain metal or can be free of metals. Also,the feed it can also have high or low nitrogen or sulfur impurities.

The conversion of hydrocarbon feeds can take place in any convenientmode, for example, in fluidized bed, moving bed, or fixed bed reactorsdepending on the types of process desired.

The catalysts of the present invention by itself or in combination withone or more catalytically active substances can be used for a variety oforganic, e.g., hydrocarbon compound conversion processes. Examples ofsuch hydrocarbon conversion processes include, as non-limiting examples,the following:

(A) The catalytic cracking of a naphtha feed to produce light olefins.Typical reaction conditions include from about 500° C. to about 750° C.,pressures of subatmospheric or atmospheric, generally ranging up toabout 10 atmospheres (gauge) and residence time (volume of the catalyst,feed rate from about 10 milliseconds to about 10 seconds.

(B) The catalytic cracking of high molecular weight hydrocarbons tolower weight hydrocarbons. Typical reaction conditions for catalyticcracking include temperatures of from about 400° C. to about 700° C.,pressures of from about 0.1 atmosphere (bar) to about 30 atmospheres,and weight hourly space velocities of from about 0.1 to about 100 hr⁻¹.

(C) The transalkylation of aromatic hydrocarbons in the presence ofpolyalkylaromatic hydrocarbons. Typical reaction conditions include atemperature of from about 200° C. to about 500° C., a pressure of fromabout atmospheric to about 200 atmospheres, a weight hourly spacevelocity of from about 1 to about 1000 hr⁻¹ and an aromatichydrocarbon/polyalkylaromatic hydrocarbon mole ratio of from about 1/1to about 16/1.

(D) The isomerization of aromatic (e.g., xylene) feedstock components.Typical reaction conditions for such include a temperature of from about230° C. to about 510° C., a pressure of from about 0.5 atmospheres toabout 50 atmospheres, a weight hourly space velocity of from about 0.1to about 200 and a hydrogen/hydrocarbon mole ratio of from about 0 toabout 100.

(E) The dewaxing of hydrocarbons by selectively removing straight chainparaffins. The reaction conditions are dependent in large measure on thefeed used and upon the desired pour point. Typical reaction conditionsinclude a temperature between about 200° C. and 450° C., a pressure upto 3,000 psig and a liquid hourly space velocity from 0.1 to 20.

(F) The alkylation of aromatic hydrocarbons, e.g., benzene andalkylbenzenes, in the presence of an alkylating agent, e.g., olefins,formaldehyde, alkyl halides and alcohols having 1 to about 20 carbonatoms. Typical reaction conditions include a temperature of from about100° C. to about 500° C., a pressure of from about atmospheric to about200 atmospheres, a weight hourly space velocity of from about 1 hr⁻¹ toabout 100 hr⁻¹ and an aromatic hydrocarbon/alkylating agent mole ratioof from about 1/1 to about 20/1.

(G) The alkylation of aromatic hydrocarbons, e.g., benzene, with longchain olefins, e.g., C₁₄ olefin. Typical reaction conditions include atemperature of from about 50° C. to about 200° C., a pressure of fromabout atmospheric to about 200 atmospheres, a weight hourly spacevelocity of from about 2 hr⁻¹ to about 2000 hr⁻¹ and an aromatichydrocarbon/olefin mole ratio of from about 1/1 to about 20/1. Theresulting product from the reaction are long chain alkyl aromatics whichwhen subsequently sulfonated have particular application as syntheticdetergents;

(H) The alkylation of aromatic hydrocarbons with light olefins toprovide short chain alkyl aromatic compounds, e.g., the alkylation ofbenzene with propylene to provide cumene. Typical reaction conditionsinclude a temperature of from about 10° C. to about 200° C., a pressureof from about 1 to about 30 atmospheres, and an aromatic hydrocarbonweight hourly space velocity (WHSV) of from 1 hr⁻¹ to about 50 hr⁻¹;

(I) The hydrocracking of heavy petroleum feedstocks, cyclic stocks, andother hydrocrack charge stocks. The catalyst will contain an effectiveamount of at least one hydrogenation component of the type employed inhydrocracking catalysts.

(J) The alkylation of a reformate containing substantial quantities ofbenzene and toluene with fuel gas containing short chain olefins (e.g.,ethylene and propylene) to produce mono- and dialkylates. Typicalreaction conditions include temperatures from about 100° C. to about250° C., a pressure of from about 100 to about 800 psig, a WHSV-olefinfrom about 0.4 hr⁻¹ to about 0.8 hr⁻¹, a WHSV-reformate of from about 1hr⁻¹ to about 2 hr⁻¹ and, optionally, a gas recycle from about 1.5 to2.5 vol/vol fuel gas feed.

(K) The alkylation of aromatic hydrocarbons, e.g., benzene, toluene,xylene, and naphthalene, with long chain olefins, e.g., C₁₄ olefin, toproduce alkylated aromatic lube base stocks. Typical reaction conditionsinclude temperatures from about 100° C. to about 400° C. and pressuresfrom about 50 to 450 psig.

(L) The alkylation of phenols with olefins or equivalent alcohols toprovide long chain alkyl phenols. Typical reaction conditions includetemperatures from about 100° C. to about 250° C., pressures from about 1to 300 psig and total WHSV of from about 2 hr⁻¹ to about 10 hr⁻¹.

(M) The conversion of light paraffins to olefins and/or aromatics suchas is disclosed in U.S. Pat. No. 5,283,563, which is hereby incorporatedby reference. Typical reaction conditions include temperatures fromabout 425° C. to about 760° C. and pressures from about 10 to about 2000psig.

(N) The conversion of light olefins to gasoline, distillate and luberange hydrocarbons. Typical reaction conditions include temperatures offrom about 175° C. to about 375° C and a pressure of from about 100 toabout 2000 psig.

(O) Two-stage hydrocracking for upgrading hydrocarbon streams havinginitial boiling points above about 200° C. to premium distillate andgasoline boiling range products or as feed to further fuels or chemicalsprocessing steps in a first stage using in the first stage the catalystcomprising one or more catalytically active substances, e.g., a GroupVIII metal, and the effluent from the first stage would be reacted in asecond stage using a second catalyst comprising one or morecatalytically active substances, e.g., a Group VIII metal, as thecatalyst. Typical reaction conditions include temperatures from about315° C. to about 455° C., a pressure from about 400 to about 2500 psig,hydrogen circulation of from about 1000 to about 10,000 SCF/bbl and aliquid hourly space velocity (LHSV) of from about 0.1 to 10;

(P) A combination hydrocracking/dewaxing process in the presence of thecatalyst comprising a hydrogenation component. Typical reactionconditions including temperatures from about 350° C. to about 400° C.,pressures from about 1400 to about 1500 psig, LHSVs from about 0.4 toabout 0.6 and a hydrogen circulation from about 3000 to about 5000SCF/bbl.

(Q) The reaction of alcohols with olefins to provide mixed ethers, e.g.,the reaction of methanol with isobutene and/or isopentene to providemethyl-t-butyl ether (MTBE) and/or t-amyl methyl ether (TAME). Typicalconversion conditions including temperatures from about 20° C. to about200° C., pressures from 2 to about 200 atm, WHSV (gram-olefin per hourgram-catalyst) from about 0.1 hr⁻¹ to about 200 hr⁻¹ and an alcohol toolefin molar feed ratio from about 0.1/1 to about 5/1.

(R) The disproportionation of toluene to make benzene and paraxylene.Typical reaction conditions including a temperature of from about 200°C. to about 760° C., a pressure of from about atmospheric to about 60atmosphere (bar), and a WHSV of from about 0.1 hr⁻¹ to about 30 hr⁻¹.

(S) The conversion of naphtha (e.g. C6-C10) and similar mixtures tohighly aromatic mixtures. Thus, normal and slightly branched chainedhydrocarbons, preferably having a boiling range above about 40° C., andless than about 200° C., can be converted to products having asubstantial higher octane aromatics content by contacting thehydrocarbon feed with the catalyst at a temperature in the range of fromabout 400° C. to 600° C., preferably 480° C. to 550° C. at pressuresranging from atmospheric to 40 bar, and liquid hourly space velocities(LHSV) ranging from 0.1 to 15.

(T) The adsorption of alkyl aromatic compounds for the purpose ofseparating various isomers of the compounds.

(U) The conversion of oxygenates, e.g., alcohols, such as methanol, orethers, such as dimethylether, or mixtures thereof to hydrocarbonsincluding olefins and aromatics with reaction conditions including atemperature of from about 275° C. to about 600° C., a pressure of fromabout 0.5 atmosphere to about 50 atmospheres and a liquid hourly spacevelocity of from about 0.1 to about 100;

(V) The oligomerization of straight and branched chain olefins havingfrom about 2 to about 5 carbon atoms. The oligomers which are theproducts of the process are medium to heavy olefins which are useful forboth fuels, i.e., gasoline or a gasoline blending stock, and chemicals.The oligomerization process is generally carried out by contacting theolefin feedstock in a gaseous state phase with the catalyst at atemperature in the range of from about 250° C. to about 800° C., a LHSVof from about 0.2 to about 50 and a hydrocarbon partial pressure of fromabout 0.1 to about 50 atmospheres. Temperatures below about 250° C. maybe used to oligomerize the feedstock when the feedstock is in the liquidphase when contacting the catalyst. Thus, when the olefin feedstockcontacts the catalyst in the liquid phase, temperatures of from about10° C. to about 250° C. may be used.

(W) The conversion of C₂ unsaturated hydrocarbons (ethylene and/oracetylene) to aliphatic C₆₋₁₂ aldehydes and converting said aldehydes tothe corresponding C₆₋₁₂ alcohols, acids, or esters.

(X) The isomerization of ethylbenzenes to xylenes. Exemplary conditionsinclude a temperature from 600°-800° F., a pressure from 50 to 500 psig,and a LHSV of from about 1 to about 10.

In general, therefore, catalytic conversion conditions over a catalystcomprising the catalyst include a temperature of from about 100° C. toabout 760° C., a pressure of from about 0.1 atmosphere (bar) to about200 atmospheres (bar), a weight hourly space velocity of from about 0.08hr⁻¹ to about 2,000 hr⁻¹.

Although many hydrocarbon conversion processes prefer that the secondABMS crystals have lower acidity to reduce undesirable reactionsexternal to the first ABMS crystals, some processes prefer that thesecond ABMS crystals have higher acidity, e.g., the acidity be tailoredso as to catalyze desirable reactions. Such processes are of two types.In the first type, the acidity and the structure type of the second ABMSis tailored to match the acidity and the crystallographic type of thefirst ABMS. By doing so, the catalytically active material per weight offormed catalyst will be increased thereby resulting in increasedapparent catalyst activity. Such a catalyst would also be benefited bythe greater adsorption, e.g., accessibility and reduced non-selectivesurface acidity.

The second type of process that can be benefited by tailoring theacidity of the second ABMS phase is one where two or more reactions aretaking place within the ABMS catalyst. In such a process, the acidityand/or structure type of the second phase ABMS may be tailored so thatit is different than that of the first ABMS, but does not have to beessentially void of acidic sites. Such a catalyst would be comprised oftwo different ABMS that could each be separately tailored to promote orinhibit different reactions. A process using such a catalyst would notonly benefit from greater apparent catalyst activity, greater ABMSaccessibility, and reduced non-selective surface acidity possible withthe catalyst, it would also benefit from a tailored product.

Combined xylene isomerization/ethylbenzene dealkylation processes wouldbenefit from this type of catalyst. An isomerization/ethylbenzenedealkylation catalyst could be tailored such that ethylbenzenedealkylation would primarily occur within the first ABMS crystals, andxylenes isomerization would primarily occur within the second ABMScrystals. By tailoring a catalyst in this way, a balance between the tworeactions can be achieved that could not otherwise be achieved with acatalyst containing only one ABMS.

The catalysts of the present invention had particular application in theprocedures set forth below.

A process where long straight chain hydrocarbons contained in ahydrocarbon stream of high pour point and high viscosity are isomerizedto branched hydrocarbons via contact with an ALPO bound SAPO catalyst togive a hydrocarbon fluid with reduced pour point and lower viscosity.The SAPO component is an intermediate pore size molecular sieve and hasan active metal for hydrogenation/dehydrogenation reactions and isacidic. The ALPO component can be either the same structural type ordifferent and has little or no metal component and is non-acidic. Thehydrocarbon is contacted with the catalyst at 150-650° C. in thepresence of hydrogen gas at 15-3000 psig pressure with a WHSV of 0.1-20hr⁻¹.

A process where C₂-C₅ paraffins and olefins are converted tomono-nuclear aromatic compounds by contacting the paraffins with an ALPObound SAPO catalyst at 400-700° C. at a pressure of 1-100 atmospheresand WHSV of 0.1-200 hr⁻¹. The SAPO component is a medium pore molecularsieve and may or may not contain a metal oxide component such as ZnO orGa₂O₃. The ALPO material may or may not be the same structural type andmay contain metal oxide components such as ZnO or Ga₂O₃.

A process to convert methanol to light olefins where the methanol iscontacted with the ALPO bound SAPO at 400-600° C. at pressure of 1-100atmospheres sometimes in the presence of a diluent such as steam with aWHSV or 0.1-100 hr⁻¹. At least one of the ALPO or SAPO components shouldhave an 8-ring pore opening such as SAPO-34, SAPO-17, or ALPO-17. Theother component could be also have an 8-ring pore opening or could beeither 10 or 12 ring openings. Possible non-limiting combinations areALPO-17 bound SAPO-11 or ALPO-17 bound SAPO-34.

The catalysts of the present invention find particular application inreactions involving aromatization and/or dehydrogenation. They areparticularly useful in a process for the dehydrocyclization and/orisomerization of acyclic hydrocarbons in which the hydrocarbons arecontacted at a temperature of from 370° C. to 600° C., preferably from430° C. to 550° C. with the catalysts, preferably having at least 90% ofthe exchangeable cations as alkali metal ions and incorporating at leastone Group VIII metal having dehydrogenating activity, so as to convertat least part of the acyclic hydrocarbons into aromatic hydrocarbons.

The aliphatic hydrocarbons may be straight or branched chain acyclichydrocarbons, and particularly paraffins such as hexane, althoughmixtures of hydrocarbons may also be used such as paraffin fractionscontaining a range of alkanes possibly with minor amounts of otherhydrocarbons. Cycloaliphatic hydrocarbon such as methylcyclopentane mayalso be used. In a preferred aspect the feed to a process for preparingaromatic hydrocarbons and particularly benzene comprises hexanes. Thetemperature of the catalytic reaction may be from 370° C. to 600° C.,preferably 430° C. to 550° C. and preferably pressures in excess ofatmospheric are used, for example up to 2000 KPa, more preferably 500 to1000 KPa. Hydrogen is usually employed in the formation of aromatichydrocarbons preferably with a hydrogen to feed ratio of less than 10.

The following examples illustrate the invention:

EXAMPLE 1

I. Catalyst A—ALPO-5 Bound SAPO-34

SAPO-34 bound by 30% by weight alumina was formed into AIPO-5 boundSAPO-34 as follows:

Amounts of 4.18 grams of 85% aqueous H₃PO₄, 10.78 grams of water, and2.65 grams of tripropylamine (TPA) were added to a 300 ml Teflon linedautoclave in the order listed. The mixture was stirred to give ahomogeneous solution. Next, 10 grams of dried extrudates ({fraction(1/16)}″ diameter) of the alumina bound SAPO-34 were added to thecontents in the autoclave. The extrudates were completely covered by theliquid. The molar composition of the synthesis mixture was:

TPA/Al₂O₃/P₂O₅/H₂O of 0.63/1.0/0.62/23.4

In the mixture, the alumina accounts for only the alumina binder of theextrudate and the P₂O₅ accounts for only 85% aqueous H₃PO₄. Theautoclave was sealed and the mixture was heated in 2 hours to 200° C.and held without stirring for 24 hours at 200° C. The autoclave wascooled to room temperature and the mother liquor was decanted. Theextrudates were washed with de-ionized water until the conductivity ofthe filtrate was less than 100 micro-Siemens. XRD analysis showedtypical patterns for both SAPO-34 and ALPO-5.

II. Catalyst B—ALPO-11 Bound SAPO-34

SAPO-34 bound by 25% by weight alumina was formed into ALPO-11 boundSAPO-34 as follows:

Amounts of 6.36 grams of 85% aqueous H₃PO₄, 18.02 grams of water, and2.82 grams of dipropylamine (DPA) were added to a 100 ml teflon linedautoclave in the order listed. The mixture was stirred to give ahomogeneous solution. Next, 15.00 grams of dried extrudates ({fraction(1/16)}″ diameter) of the alumina bound SAPO-34 were added to thecontents in the autoclave. The extrudates were completely covered by theliquid. The molar composition of the synthesis mixture was:

DPA/Al₂O₃/P₂O₅/H₂O of 0.76/0.75/1.0/30.9

In the mixture, the Al₂O₃ accounts for only the alumina binder of theextrudate and the P₂O₅ accounts for only the 85% aqueous H₃PO₄. Theautoclave was sealed and heated in 2 hours to 200° C. and held withoutstirring for 22 hours at 200° C. The autoclave was cooled to roomtemperature and the mother liquor was decanted. The extrudates werewashed with de-ionized water until the conductivity of the filtrate wasless than 100 micro-Siemens. XRD analysis showed typical patterns forboth SAPO-34 and ALPO-11.

III. Catalyst C—ALPO-17 Bound SAPO-34

SAPO-34 bound by 25% by weight alumina was formed into AIPO-5 boundSAPO-34 as follows:

Amounts of 6.35 grams of 25% aqueous H₃PO₄, 17.60 grams of water, and2.77 grams of cyclohexalamine were added to a 300 ml Teflon linedautoclave in the order listed. The mixture was stirred to give ahomogeneous solution. Next, 15.02 grams of dried extrudates ({fraction(1/16)}″ diameter) of the alumina bound SAPO-34 were added to thecontents in the autoclave. The extrudates were completely covered by theliquid. The molar composition of the synthesis mixture was:

1.00R₂O₅/1.0R/1.00Al₂O₃/39H₂O

In the mixture, the alumina accounts for only the alumina binder of theextrudate and the P₂O₅ accounts for only 25% aqueous H₃PO₄. Theautoclave was sealed and the mixture was heated in 2 hours to 200° C.and held for 48 hours at 200° C. The autoclave was cooled to roomtemperature, a small sample of extrudate removed, and then the mixturewas heated to 200° C. in 2 hours and held at 200° C. for another 48hours. The extrudates were allowed to cool and were washed 4 times with800 ml of water. The conductivity of the last wash water was less than26 μS/cm. The extrudates were then dried at 120° C. The amount ofextrudates recovered was 17.3 grams. XRD analysis showed typicalpatterns for both SAPO-34 and ALPO-5.

EXAMPLE 2

Catalyst A, Catalyst B, and Catalyst C were tested for use in theconversion of oxygenates to olefins. The tests were carried out usingthe following procedure: 5.0 cc (approximately 2.7 grams) of eachcatalyst was mixed with 15 cc quartz beads and loaded into a ¾″ outerdiameter 316 stainless steel tubular reactor which was heated bythree-zone electric furnaces. The first zone acted as the preheatingzone, vaporized the feed. The temperature of the center zone of thefurnace was adjusted to 450° C. and the pressure was maintained at 1atm. The reactor was purged first with nitrogen at 50 cc/min flow ratefor 30 minutes. The feed had a 4:1 molar ratio of water to methanol andwas pumped into the reactor at a rate calibrated to give a flow rate ofabout 0.7 hr⁻¹ WHSV. The effluent was analyzed at pre-determinedintervals by an on-line gas chromatography fitted with both a thermalconductivity detector and a flame ionization detector. The results ofthese tests are shown below in Table IV:

TABLE IV Olefins Yield Catalyst A Catalyst B Catalyst C Conversion (wt.%) Methane 5.7 1.6 1.5 Ethylene 24 45 47 Propylene 41 38 37 C₄ 27 15 14

The data shows that the catalysts have good ethylene and propyleneselectivity and by tailoring the catalyst, product distribution can bevaried.

What is claimed is:
 1. An ABMS bound ABMS catalyst which does notcontain significant amounts of amorphorous binder and comprises: (a)first crystals of a first ABMS, and (b) a binder comprising secondcrystals of a second ABMS, said second crystals binding together saidfirst crystals.
 2. The catalyst recited in claim 1, wherein said firstcrystals of said first ABMS have an average particle size greater thanabout 0.1 micron.
 3. The catalyst recited in claim 2, wherein saidsecond crystals of said second ABMS have an average particle size thatis less than said first crystals of said first ABMS.
 4. The catalystrecited in claim 3, wherein said second crystals are intergrown and format least a partial coating on said first crystals.
 5. The catalystrecited in claim 3, wherein said first ABMS is a structure type selectedfrom the group consisting of VFI, AET, AFI, AFO, ATS, FAU, AEL, AFR,AFS, AFY, ATO, AFY, APD, AEI, AFT, APC, ATN, ATT, ATV, AWW, BIK, CAS,CHA, CHI, DAC, DDR, EDI, ERI, GOO, KFI, LEV, LOV, LTA, MON, PAU, PHI,RHO, ROG, and THO.
 6. The catalyst recited in claim 5, wherein saidsecond ABMS is a structure type selected from the group consisting ofVFI, AET, AFI, AFO, ATS, AFO, FAU, AEL, AFR, AFS, AFY, ATO, AFY, APD,AEI, AFT, APC, ATN, ATT, ATV, AWW, BIK, CAS, CHA, CHI, DAC, DDR, EDI,ERI, GOO, KFI, LEV, LOV, LTA, MON, PAU, PHI, RHO, ROG, and THO.
 7. Thecatalyst recited in claim 6, wherein said second ABMS has lower aciditythan the first ABMS.
 8. The catalyst recited in claim 6, wherein saidsecond ABMS has higher acidity than the first ABMS.
 9. The catalystrecited in claim 6, wherein said first ABMS and said second ABMS havedifferent structure types.
 10. The catalyst recited in claim 6, whereinsaid first ABMS and said second ABMS are the same type.
 11. The catalystrecited in claim 6, wherein said first crystals have an average particlesize of from about 1 to 6 microns.
 12. The catalyst recited in claim 11,wherein said second crystals have an average particle size of from about0.1 to about 0.5 microns.
 13. The catalyst recited in claim 12, whereinsaid second crystals are intergrown and form at least a partial coatingon said first crystals.
 14. The catalyst recited in claim 7, whereinsaid second ABMS is ALPO.
 15. The catalyst recited in claim 14, whereinsaid first ABMS is SAPO, MeAPO, MeAPSO, ELAPO, or ELAPSO.
 16. Thecatalyst recited in claim 14, wherein said first ABMS is SAPO.
 17. Thecatalyst recited in claim 16, wherein said catalyst contains less than5% by weight of non-molecular sieve binder based on weight of said firstABMS and said second ABMS.
 18. The catalyst recited in claim 17, whereinsaid second crystals of said second ABMS are present in an amount in therange of from about 10 to about 60% by weight based on the weight of thefirst ABMS.
 19. The catalyst recited in claim 3, wherein said first ABMSand said second ABMS are independently selected from the groupconsisting of ALPO-8, ALPO-41, SAPO-37, ALPO-37, SAPO-31, SAPO-40,SAPO-41, ALPO-5, SAPO-5, ALPO-54, MAPO-36, SAPO-40, SAPO-11, ALPO-31,ALPO-11, ALPO-17, ALPO-18, ALPO-52, ALPO-22, and ALPO-25.
 20. Thecatalyst recited in claim 3, wherein said first ABMS is SAPO-37,SAPO-40, SAPO-5, MAPO-36, and SAPO-11.
 21. The catalyst recited in claim3, wherein said first ABMS is SAPO-34, SAPO-11, GaSAPO-11, ZnSAPO-11,SAPO-17, NiSAPO-34, or SAPO-5.
 22. The catalyst recited in claim 20,wherein said second ABMS is ALPO-17, ALPO-18, ALPO-11, ALPO-5, ALPO-41,GaALPO-11, or ZnALPO-11.
 23. The catalyst recited in claim 3, whereinsaid first ABMS is SAPO-34 and said second ABMS is ALPO-5, ALPO-17, andALPO-11.
 24. The catalyst recited in claim 2, wherein said first ABMSand said second ABMS have different structure types.
 25. The catalystrecited in claim 2, wherein said first crystals have an average particlesize of from about 1 to 6 microns.
 26. The catalyst recited in claim 25,wherein said second crystals have an average particle size of from about0.1 to about 0.5 microns.